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J Denton

Publications and source records attributed to J Denton.

At least 55 records · Page 3Linked to original sources
PubMed1991

Diagnostic value of synovial fluid microscopy: a reassessment and rationalisation.

This study is in two parts. In the first synovial fluid from 1892 patients with 14 different arthropathies was examined microscopically. Crystals of different types were identified and the disease distribution of these and various cell types, including several not previously reported in synovial fluid, have been described. These features have been used to derive a series of microscopic diagnostic criteria for each arthropathy. The criteria have been used in the second part of the study to examine synovial fluids from 200 patients without knowledge of any clinical diagnosis. Cytological and clinical diagnoses were compared at the end of the study. Matching diagnoses were made in 71 (35.5%) and a short list of differential diagnoses (based on cytological criteria), which included the clinical diagnosis, was made in a further 43 (21.5%). Of the rest, 63 (31.5%) were correctly described as inflammatory or non-inflammatory and in five (2.5%) no diagnosis could be made. Only in seven cases (3.5%) was an inaccurate (false positive) cytological diagnosis made. The results indicate that synovial fluid microscopy is a potentially more important diagnostic screening test in rheumatological and orthopaedic practice than it would at first appear from published reports.

Adult↗
PubMed1990

Aluminium deposition in bone after contamination of drinking water supply.

Two healthy individuals who drank water accidentally contaminated at source with aluminium sulphate solution were investigated 6-7 months later. Bone biopsy specimens showed discrete lines of positive staining for aluminium, the distribution being compatible with acute exposure some months previously. These findings show that under certain conditions normal individuals can absorb aluminium via the gut, and that such aluminium can be deposited in bone.

Adult↗
PubMed1989

Synthesis of the active metabolite of vitamin D, 1,25(OH)2D3, by synovial fluid macrophages in arthritic diseases.

Synthesis of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has been shown in cells from knee joint synovial fluid of 20 patients with inflammatory rheumatoid disease, reactive or psoriatic arthritis, or gout, all of which had high synovial fluid cell counts, and by cells from a patient with aseptic necrosis of a femoral condyle after short term (less than 24 hours) or long term (seven days) primary culture. Cells from 18 patients with inflammatory arthritis, five of which had low synovial fluid cell counts and cells from six patients with osteoarthritis were unable to synthesise this metabolite from 25-hydroxyvitamin D3 (25(OH)D3). Macrophages are believed to be the cells responsible for synthesising 1,25(OH)2D3 because these were significantly more numerous in samples that formed 1,25(OH)2D3; they were also the predominant cell type present in the aseptic necrosis sample and the only cell type present in preparations maintained for one week in monolayer culture.

Arthritis↗
PubMed1988

Comparison of serial synovial fluid cytology in rheumatoid arthritis: delineation of subgroups with prognostic implications.

Serial synovial fluid samples were obtained from patients with rheumatoid arthritis and analysed cytologically. Positive correlations in the serial samples between proportions of polymorphs and ragocytes were found. Based upon the serial synovial fluid cytology, distinct subgroups of rheumatoid joints emerged. Comparison of clinical findings in these subgroups showed that the joints with high ragocyte proportion had a significantly poorer outcome. This study therefore identifies two distinct subgroups of rheumatoid joints on the basis of the nature of the cellular reaction within the joint fluid, which usually holds true during subsequent clinical relapse. Identification of these groups may have prognostic significance.

Adolescent↗
PubMed1988

Retained surgical swab debris in post-laminectomy arachnoiditis and peridural fibrosis.

We examined soft tissue biopsies from 26 patients with symptomatic nerve root fibrosis and arachnoiditis after a previous laminectomy. Dense fibrous connective tissue was found about the nerve roots and in 14 cases (55%) fibrillar foreign material was seen within it. This material had the histochemical characteristics of cotton fibres from swabs and neurosurgical patties. In two other cases nerve root fibrosis was associated with residual radiopaque lipid thought to derive from earlier myelography. Our findings suggest that risks may be associated with the introduction of foreign material into the vertebral canal, and that microscopic fragments of surgical swabs and patties may have a role in the pathogenesis of postoperative periradicular fibrosis.

Adult↗
PubMed1985

Disease distribution of synovial fluid mast cells and cytophagocytic mononuclear cells in inflammatory arthritis.

Three hundred and twenty-one synovial fluids from the knees of patients with six different inflammatory arthropathies have been examined for the presence of cytophagocytic monocytes (CPM) and mast cells. Both cell types were seen independently in many of the fluids examined but were found together only in those patients with Reiter's disease, psoriatic arthritis, ankylosing spondylitis, and enteropathic arthritis. These four disease groups also contain the highest proportion of patients with mast cells in their synovial fluids and those individuals with the greatest number of synovial fluid CPM. Criteria have been developed from these observations which may be employed in the differential diagnosis of inflammatory arthropathies.

Arthritis↗
PubMed1984

Anticoagulant activities of heparin oligosaccharides and their neutralization by platelet factor 4.

Oligosaccharides of well-defined molecular size were prepared from heparin by nitrous acid depolymerization, affinity chromatography on immobilized antithrombin III (see footnote on Nomenclature) and gel chromatography on Sephadex G-50. High affinity (for antithrombin III) octa-, deca-, dodeca-, tetradeca-, hexadeca- and octadeca-saccharides were prepared, as well as oligosaccharides of larger size than octadecasaccharide. The inhibition of Factor Xa by antithrombin III was greatly accelerated by all of these oligosaccharides, the specific anti-Factor Xa activity being invariably greater than 1300 units/mumol. The anti-Factor Xa activity of the decasaccharide was not significantly decreased in the presence of platelet factor 4, even at high platelet factor 4/oligosaccharide ratios. Measurable but incomplete neutralization of the anti-Factor Xa activities of the tetradeca- and hexadeca-saccharides was observed, and complete neutralization of octadeca- and larger oligo-saccharides was achieved with excess platelet factor 4. The octa-, deca-, dodeca-, tetradeca- and hexadeca-saccharides had negligible effect on the inhibition of thrombin by antithrombin III, whereas specific anti-thrombin activity was expressed by the octadeca-saccharide and by the larger oligosaccharides. An octadecasaccharide is therefore the smallest heparin fragment (prepared by nitrous acid depolymerization) that can accelerate thrombin inhibition by antithrombin III. The anti-thrombin activities of the octadecasaccharide and larger oligosaccharides were more readily neutralized by platelet factor 4 than were their anti-Factor Xa activities. These findings are compatible with two alternative mechanisms for the action of platelet factor 4, both involving the binding of the protein molecule adjacent to the antithrombin III-binding site. Such binding results in either steric interference with the formation of antithrombin III-proteinase complexes or in displacement of the antithrombin III molecule from the heparin chain.

Anticoagulants↗
PubMed1984

Detection and distribution of aluminium in bone.

The distribution of aluminium has been investigated using a new histochemical technique in transiliac bone biopsy specimens from 20 patients with aluminium related bone disease and 17 with other metabolic bone diseases. The method, which employs solochrome azurine at acid pH (acid solochrome azurine), showed a wider distribution of aluminium within cortical and trabecular bone than other histochemical techniques. The results compared well with atomic absorption spectrophotometric analysis of these biopsy specimens. Wavelength dispersive electron probe analysis of serial sections validated the procedure. The method has certain advantages over both these analytical techniques.

Aluminum↗
PubMed1983

Binding of platelet factor 4 to heparin oligosaccharides.

Heparin fractions of differing Mr (7800-18 800) prepared from commercial heparin by gel filtration and affinity chromatography on immobilized anti-thrombin III had specific activities when determined by anti-Factor Xa and anti-thrombin assays that ranged from 228 to 448 units/mg. The anti-Factor Xa activity of these fractions could be readily and totally neutralized by increasing concentrations of platelet factor 4 (PF4). That these fractions bound to immobilized PF4 was indicated by the complete binding under near physiological conditions of 3H-labelled unfractionated commercial heparin. An anti-thrombin III-binding oligosaccharide preparation (containing predominantly eight to ten saccharide units), prepared by degradation of heparin with HNO2 had high (800 units/mg) anti-Factor Xa, but negligible anti-thrombin, specific activity. The anti-Factor Xa activity of this material could not be readily neutralized by PF4, and the 3H-labelled oligosaccharides did not completely bind to immobilized PF4. A heterogeneous anti-thrombin III-binding preparation containing upwards of 16 saccharides had anti-thrombin specific activity of just less than one-half the anti-Factor Xa specific activity. This material was completely bound to immobilized PF4 and was eluted with similar concentrations of NaCl to those that were required to elute unfractionated heparins from these columns. Furthermore, increasing concentrations of PF4 neutralized the anti-Factor Xa activity of this material in a manner similar to that of unfractionated heparin. It is concluded that heparin oligosaccharides require saccharide units in addition to the anti-thrombin III-binding sequence in order to fully interact with PF4.

Antithrombins↗
PubMed1983

The synovium and synovial fluid in multicentric reticulohistiocytosis--a light microscopic, electron microscopic and cytochemical analysis of one case.

The synovium and synovial fluid have been studied in a patient with multicentric reticulohistiocytosis. Previously unreported histochemical, immunocytochemical and ultrahistochemical findings are presented and their relevance to the aetiology and pathogenesis are discussed. The synovial fluid analysis in this disease is characteristic and may be helpful in its early diagnosis.

Acid Phosphatase↗
PubMed1983

Treatment of fracturing renal osteodystrophy by desferrioxamine.

Aluminium removal by desferrioxamine chelation has been demonstrated in three long-term haemodialysis patients with dialysis encephalopathy and fracturing renal osteodystrophy. Aluminium concentrations in serum and in both bone marrow and bone trabeculae, determined separately in transiliac biopsy specimens, fell significantly over the treatment period. Bone aluminium removal was confirmed by specific histochemical staining. In two patients osteomalacia disappeared, and in two patients osteitis fibrosa emerged but improved in one following vitamin D therapy. We conclude that desferrioxamine is capable of mobilising aluminium from bone and that the calcification defect in fracturing renal osteodystrophy may be overcome.

Adult↗